질소 비료 시용량에 따른 세물차의 수량 및 품질 = Effect of Nitrogen Fertilizer Levels on Yield and Quality of 3rd harvested Leaves of Tea

다국어 초록 (Multilingual Abstract)

The reasonable level of nitrogen fertilizes are a key factor to reduce environmental contamination as well as to increase crop yield and quality. As the application amount of nitrogen fertilizer increased, the yield of tea leaves, the contents of vitamin C and chlorophyll increased; however, excessive level 150 kg/l0a showed decreaed the yield of tea leaves. (60 kg/l0a : 440 kg ⇒ 150 kg/l0a : 465kg) On the other hand, the increased level of nitrogen fertilizer did not show difference in contents of total nitrogen, total free amino acid, caffeine and tannin, while those contents were increased or decreased to 60 kg/10a, but showed counter appearance from 72 kg/10a. As the application amount of nitrogen fertilizer increased, contents of 4 anions except F⁻ and 4 cations except Ca²⁺ were increased. Eleven kinds of amino acids was isolated from third harvested leaves of tea where the content of theanine occupied over 50% ; from 420 to 572 mg/100g. The contents of fatty acids and catechin did not show correlation with application level of nitrogen fertilizer. The content of fatty acid was produced 1,614~1,801mg/100g, and content of catechin was produced 12.83~13.83%. In scoring test, 60 kg/l0a treatmemt was 1.0~7.0 point higher compared to other treatments. Consequently, 60 kg/l0a is considered to be best level of nitrogen fertilizer in terms of increase crop yield, quality, and scoring test.